Diagnostic endoscopy is a common procedure in the United States and other countries, perhaps being second only to interventional cardiology in generating hospital revenue.
Traditional endoscopy utilizes flexible endoscopes that are steered by internal tension wires. These probes typically include means for illumination, lavage, and imaging (usually with a CCD camera chip at the distal tip), as well as a working channel through which, for example, biopsy forceps, snares, and fulguration probes can be introduced. Such devices allow physicians to see and treat polyps and other common disorders of the alimentary, gastrointestinal, and respiratory tracts.
Even after 20 years of refinement, present day endoscopes are expensive, bulky and stiff. For example, conventional steering-cable-based schemes allow for control of the shape of only the most distal portion of the endoscope. As a result, a long, relatively stiff portion of the endoscope follows the working tip. The resultant forces imparted to sensitive endolumenal tissue result in the need for sedation. Conventional endoscopes are also subject to cross-contamination, unless they are cleaned and disinfected carefully.
Annual colonoscopic examinations are routinely recommended for males over 50 years of age, but only a small fraction of this population receives such an annual examination, because of the discomfort and the perceived risks associated with the examination. Moreover, present day endoscopic examinations almost always require sedation, for example, using a powerful amnesiac such as midazolam hydrochloride (e.g. Versed® owned by Hoffmann LaRoche). This sedation accounts for approximately half of the costs associated with the overall endoscopic procedure.
There have been several research projects aimed at “sedationless” endoscopy using designs that clamp-and-pull the endoscope using distal inchworm or suck-and-step mechanisms. These approaches do not, however, overcome the disadvantage that the balance of the endoscope is dragged along after the distal end.
There is thus a need for a new generation of endoscopes that can navigate the anatomic tract with minimal tugging and pulling on the endothelium, thus reducing the pain, risk and need for sedation that is associated with endoscopic examinations. This will in turn lead to a decrease in the cost and an increase in the frequency of endoscopic diagnosis and treatment for a wide variety of cancers and other disorders of the aerodigestive system. These and other needs are met by the present invention, as hereinafter described.